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  2. Iridium - Wikipedia

    en.wikipedia.org/wiki/Iridium

    The Willamette Meteorite, the sixth-largest meteorite found in the world, has 4.7 ppm iridium. [59] Iridium is one of the nine least abundant stable elements in Earth's crust, having an average mass fraction of 0.001 ppm in crustal rock; gold is 4 times more abundant, platinum is 10 times more abundant, silver and mercury are 80 times more ...

  3. Iridium anomaly - Wikipedia

    en.wikipedia.org/wiki/Iridium_anomaly

    The type locality of this iridium anomaly is near Raton, New Mexico. [1] [2]Iridium is a very rare element in the Earth's crust, but is found in anomalously high concentrations (around 100 times greater than normal) in a thin worldwide layer of clay marking the boundary between the Cretaceous and Paleogene periods, 66 million years ago.

  4. Alvarez hypothesis - Wikipedia

    en.wikipedia.org/wiki/Alvarez_hypothesis

    In 1980, a team of researchers led by Nobel prize-winning physicist Luis Alvarez, his son, geologist Walter Alvarez, and chemists Frank Asaro and Helen Vaughn Michel, discovered that sedimentary layers found all over the world at the Cretaceous–Paleogene boundary (K–Pg boundary, formerly called Cretaceous–Tertiary or K–T boundary) contain a concentration of iridium hundreds of times ...

  5. Abundance of elements in Earth's crust - Wikipedia

    en.wikipedia.org/wiki/Abundance_of_elements_in...

    World Book Encyclopedia, Exploring Earth. HyperPhysics, Georgia State University, Abundance of Elements in Earth's Crust. Eric Scerri, The Periodic Table, Its Story and Its Significance, Oxford University Press, 2007 "EarthRef.org Digital Archive (ERDA) -- Major Element Composition of the Core vs the Bulk Earth". earthref.org

  6. Cretaceous–Paleogene boundary - Wikipedia

    en.wikipedia.org/wiki/Cretaceous–Paleogene...

    Luis (left) and his son Walter Alvarez (right) at the K-Pg Boundary in Gubbio, Italy, 1981. In 1980, a team of researchers led by Nobel prize-winning physicist Luis Alvarez, his son, geologist Walter Alvarez, and chemists Frank Asaro and Helen Vaughn Michel discovered that sedimentary layers found all over the world at the Cretaceous–Paleogene boundary contain a concentration of iridium ...

  7. Lists of countries by mineral production - Wikipedia

    en.wikipedia.org/wiki/Lists_of_countries_by...

    Metal Largest producer Second largest producer Complete list Aluminium [6] China India List of countries by aluminium production: Bauxite [7] Australia Guinea List of countries by bauxite production

  8. Osmium - Wikipedia

    en.wikipedia.org/wiki/Osmium

    As with all of the platinum-group metals, osmium can be found naturally in alloys with nickel or copper. [56] Within Earth's crust, osmium, like iridium, is found at highest concentrations in three types of geologic structure: igneous deposits (crustal intrusions from below), impact craters, and

  9. Platinum group - Wikipedia

    en.wikipedia.org/wiki/Platinum_group

    Osmiridium is a naturally occurring alloy of iridium and osmium found in platinum-bearing river sands in the Ural Mountains and in North and South America. Trace amounts of osmium also exist in nickel-bearing ores found in the Sudbury, Ontario, region along with other platinum group metals. Even though the quantity of platinum metals found in ...